Abstract: Technologies are generally described for a scheme for computing a counting number of a keyword. In some examples, a method performed under control of a computing device may include obtaining a result of a j-th set of hash functions with regard to a key; marking a head marker into a bit array of a bloom filter based at least in part on the result of the j-th set of hash functions, if the j is zero; and marking a tail marker into the bit array of the bloom filter based at least in part on the result of the j-th set of hash functions, if the j is the same as or larger than 1.

Abstract: Technologies are generally described for a scheme for computing a counting number of a keyword. In some examples, a method performed under control of a computing device may include obtaining a result of a j-th set of hash functions with regard to a key; marking a head marker into a bit array of a bloom filter based at least in part on the result of the j-th set of hash functions, if the j is zero; and marking a tail marker into the bit array of the bloom filter based at least in part on the result of the j-th set of hash functions, if the j is the same as or larger than 1.

Abstract: Technologies are generally described for proxy key generation, and signature generation and validation. In some examples, a cryptographic key generation system may include an original key generation unit configured to generate a public key and a private key for an original signer, a proxy key generation unit configured to generate one or more proxy public keys and one or more proxy private keys for one or more proxy signers, and a transmitter configured to transmit the proxy private keys respectively to the one or more proxy signers.

Abstract: Technologies are generally described for proxy key generation, and signature generation and validation. In some examples, a cryptographic key generation system may include an original key generation unit configured to generate a public key and a private key for an original signer, a proxy key generation unit configured to generate one or more proxy public keys and one or more proxy private keys for one or more proxy signers, and a transmitter configured to transmit the proxy private keys respectively to the one or more proxy signers.

Abstract: Disclosed herein are an alphabet input device and an alphabet recognition system in a small-sized keypad. The device includes: a first keypad part comprising a plurality of buttons each of which is assigned with a symbol extracted from strokes of alphabet characters so that the alphabet characters be input by one of the buttons or a combination of two or more of the buttons; and a second keypad part comprising one or more buttons each assigned with an alphabet character having a high usage frequency. With the device, alphabet characters can be inputted in a simper and more efficient manner.

Abstract: Disclosed herein are an alphabet input device and an alphabet recognition system in a small-sized keypad. The device includes: a first keypad part comprising a plurality of buttons each of which is assigned with a symbol extracted from strokes of alphabet characters so that the alphabet characters be input by one of the buttons or a combination of two or more of the buttons; and a second keypad part comprising one or more buttons each assigned with an alphabet character having a high usage frequency. With the device, alphabet characters can be inputted in a simper and more efficient manner.

Abstract: The present invention provides a secure user session managing method and system between a client and a server connected through network in web environment. The user session managing method includes: allowing the server to receive a first HTTP request including a cookie from the client, wherein the cookie includes a client authentication value and the client authentication value is calculated by using a shared key stored in the client and session information included in a HTTP response transmitted right before to the client; comparing a server authentication value with the client authentication value included in the cookie, wherein the server authentication value is calculated by employing the session information and the shared key stored in the server; and determining a transmitter's authentication failure or success of the client according to the result of the comparison. User session can be secured by applying the challenge-response authentication algorithm to the HTTP protocol.